Securing suture during surgery can be difficult and demanding. Various suture constructs have been developed in an effort to avoid the need to tie knots in suture, particularly during arthroscopic surgery. For example, U.S. Pat. No. 6,143,017 to Thal discloses tissue fixation using a free-standing continuous suture loop that is snagged by an anchoring device. While it appears that tissue can be bound to bone according to the Thal teachings, it is not evident how to accomplish in situ surgical refinements such as adjustment of the loop length or tension on the repaired tissue. Accordingly, there exists a need in the art for improved technology for knotless tissue fixation. A need also exists for a knotless suture anchor with fenestrated configuration that promotes healing of tissue.